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How to break out of a while loop inside a function block ?

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I'm trying to break out of a while loop when a key is pressed and I've achieved this through the following code snippet -
keep = 1;
h = figure('KeyPressFcn','keep=0');
while keep
pause(0.01)
end
close(h)
I need to incorporate this into a GUI. But when this exact same code snippet is inserted into a function block, I'm no longer able to break out of the loop. Here's a code for the same -
function calibrate()
keep = 1;
h = figure('KeyPressFcn','keep=0');
while keep
pause(0.01)
end
close(h)
How do I get this to work ?
Thanks !
  1 Comment
Muthu Annamalai
Muthu Annamalai on 28 Jul 2015
Please use {} Code editor feature to make your code more readable to others.

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Accepted Answer

Jon
Jon on 28 Jul 2015
Edited: Jon on 28 Jul 2015
The search function is your friend. See https://ch.mathworks.com/matlabcentral/newsreader/view_thread/315080 for someone with the same problem, and an explanation and solution.
  2 Comments
Camile van der Heijden
Camile van der Heijden on 1 Mar 2018
Unfortunately, the newsreader link Jon referred to is no longer available. I would love to know what it said though. Does it involve using flag variables?

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More Answers (1)

Muthu Annamalai
Muthu Annamalai on 28 Jul 2015
Edited: Muthu Annamalai on 28 Jul 2015
Changing your code to,
keep = true;
h = figure('KeyPressFcn',@() keep= ~keep );
while keep
pause(0.01)
sprintf('keep = %d',keep);
end
close(h)
may work. If this doesn't work, make keep an instance of a handle class.

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